Investigating the high gradient magnetic separator function for highly efficient adsorption of lead salt onto magnetic mesoporous silica microspheres and adsorbent recycling

Abstract

Herein, a novel magnetite core decorated with amine functionalized mesoporous silica include significant surface area (ca. 885 m2 g−1) has been successfully prepared. Cetyltrimethylammonium bromide as a pore-forming agent was eliminated from the structure through a combination of two methods (calcination and modified extraction via supercritical CO2). This inventive strategy leads to form magnetic mesoporous silica microspheres that enhance the capacity of adsorption of Pb2+, (ca. 989 mg g−1). In addition, the recycling of this adsorbent from aqueous medium using high gradient magnetic separation (HGMS) was also explored and for obtaining the efficiency of separation some tests were accomplished using different matrix geometries. The separation efficiency of adsorbent via fine-matrix was more successful than a coarse matrix. Utilizing a combined arrangement of a fine and a coarse matrix, the performance of the separation was increased considerably comparing the single-stage separation chamber. About 93% of the magnetic adsorbent could be separated when the flow rate and magnitude of the magnetic field were fixed at 7.2 mL s−1 and 0.33 m T, respectively. Generally, this work was developed high efficient adsorbent for water treatment and well planned separation of adsorbent from treated water by HGMS that can be used in a large-scale.